Apparatus for drawing sheet glass



J. WHITTEIVIORE.

APPARATUS FOR DRAWING SHEET GLASS. v APPLICATION FILED IvIAII. 2. 192|.

Lgglgn I Patented All. 8, i922,

2 SHEETS-SHEET l.

I? H @u U INvEN'I-Q fa/7765 VW? /Weore I. WHITTEMORE. APPARATUS FOR DRAWING SHEET GLASS APPLICATION FILED MAR. 2, I92l.

Patented Aug. 8, 1929.

2 SHEETS-SHEET 2.

I I\I VE. I\I I- CI James WA/Yemofe EY WWW@ ATTTQNEY unuTen sTaTas PTENT @FFHCEO JAMES WHITTEMORE,

' SHEET GLASS COMPANY,

OF DETROIT, MICHIGAN, ASSIGNOR T0 THE. LIBBEY-OWNS OF TOLEDO, OHIO, A CORPORATION OF OHIO.

APPARATUS FOR DRAWING SHEET GLASS.

Application led. March 2,

To all whom t may. concern.' l

Be it known that I, JAMES WHITTEMORE, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented new and useful Improvements in Apparatus for Drawing Sheet Glass, of which the following is a specification.

This invention relates to the art of drawing sheet glass from a bath of molten glass, and more particularly is an improvementon the apparatus disclosed in the patents to Colburn, 1,248,809, issued Dec. 4, 1917, and Re. 14,794, reissued J an. 27, 1920. The same improvement is also adapted for use with horizontal sheet drawing devices, as shown in my copending application, Serial Number 336,875, filed Nov. 10, 1919, of which this present application is a division in part. i

In the apparatus disclosed by the Colburn patents, a sheet of glass is drawn vertically from a bath of molten glass, and is then bent laterally over a cooled bending roll and carried away horizontally through a suitable drawing mechanism and leer. At each edge of the sheet, adjacent the drawing point, is a pair of cooled edge rolls, between which the edge portion of the sheet is drawn to form the same. In the patents referred to, these edge rollers are driven at a peripheral speed less than the linear speed at which the sheet is being drawn, so that a down'pull or drag yis made upon the edge portions of the sheet to stretch them tight between'the source and the bending roll. This dragging action, together with the' cooling eifect of the water-cooled rollers, serves to overcome the natural tendency of the sheet to narrow as it is drawnupward. I have discovered that it is unnecessary, and sometimes undesirable to drive these rollers, but that on the contrary they may be used as idlers and driven from the sheet itself as it is drawn therebetween. The friction of the rollers and co-operating'parts, vfurnishes the necessary drag on the sheet edges, and this friction ymay be supplemented and controlled by van adjustable friction brake on one or both'ofl the roller shafts. I also contemplate using an im-y proved form of edge roll, having a series of peripheral grooves to engage the glass specification of Letters Patent. Patentcgd Aug. 8, 1922.

1921. 4Serial No. 449,092.

sheet and further counteract the tendency to narrow.

The invention will be better understood from the following detailed description and drawings of two different glass drawing systems with which my improvement is adapted for use.

In the accompanying drawings:

Fig. 1 is a rear elevation of a sheet being drawn vertically, my improved edge rolls being shown complete at one side of the sheet, and partially brroken away at the other.

Fig. 2 is a plan of the edge rolls at one side of the sheet, the sheet being shown vin horizontal section.

Fig. 3 is a vertical section through a portion of the improvement, taken lsubstan tially on the line 3-3 of Fig. 2. Part of one gear is broken away to disclose the brake.

Fig. 4 is a detail of one of the edge rolls and its shaft, partly in sectionto show the internal Water-cooling system.

Fig. 5 is a detail showing a diil'erent form of roll that may be used, and

Fig. 6 shows a central vertical longitudinal section through a horizontal sheet drawing apparatus with which my improved rolls are used.

Referring first, to the apparatus shown in Figs. 1 to 4, inclusive, a sheet of glass 1, is drawn upwardly from the molten glass 2 in receptacle 3, and is then bent horizontally over bending roll 4. rIhis merely indicates conventionally the system set forth' in detail in the Colburn patents referred to above, and need not be further described. A )air of edge rolls 5 engage each edge of the s eet near its source, and. it is between these rolls that the sheet edge is drawn and formed. The, supporting and cooling mechanism for these rolls is substantially the same as used in the prior Colburn structure alreadypreferred to,.` except that the driving connections are omitted and an adjustable friction brake substituted therefor. Each metallic roll 5 is carried at the end of a somewhat long hollow shaft 6, or 6 which exthe side portion of the ot and heating chamber 7. rI`lu'e roll 5 is a so hollow, and within the roll and the shaft 6, extends a smaller pipe 8, through which a`constant flow of cold water, or other iuid, is forced into the roll 5, from which it flows out through the shaft 6, as indicated `by the arrows in Fig. 4.

At 9 is shown a horizontal angle bar support, to which a supporting block 10` is clamped in the desired position, longitudinally of thc bar, by bolts 11. The block 10 has an undercut groove12, on the inside of a shoulder 13 at one side of the block, and at the other side is an upwardly inclined flange 14. The supporting bracket 15 for the shafts 6 is -adjustably carried on the upper facewof block 10, one side of the bracket 15 having .-1 lange 16 engaging in the groove 12, while ythe other side of the bracket is engaged by bolts 17, screwing throughv the tlange14, all as shown in Fig. 3.' After loosening the bolts 17, the bracket 15, together with the entire edge forming assembly carried thereby, may be adjusted transversely of the pot or receptacle, so as to properly engage the sheet edge, after which by tightening the bolts 17, the assembly is locked securely in place. One of each pair of shafts 6, '6? is journaled in a fixed bearing 18 projectin upwardly from bracket 15. Preferably rol er bearings (not shown) are provided for the shafts 6 and 6". The other shaft 6 of the pair is carried by a bearing l19, which has a. vertical pivot pin 20 journaled. in bracket 15. This pivot 20 allows shaft 6 to be swung laterally with respect to the companion shaft 6, so that the rolls 5 may be disengaged-from the sheet when desired. A spring 21 is confined between a downwardly projecting finger 22 on bearing 19, and an adjusting screw 23,-

mounted in the bracket 15. This spring, which is on the 4outer side of pivot v20, serves to normally press the `two rolls 5 toward one another and hold them yieldingly against the sheet edge. Stop screw 24, mounted in bracket .15, and adjustable against the outer side of finger 22, limits the possible proximity of rolls 5 to one another.

A pair of engaging gears 25, carriedby shafts 6, 6', cause them to rotate equally and in unison. Secured to the shafts 6, between gear 25 and bearing 18, is a brake drum 26, encircled by a strap brake 27. The ends of the brake band 27 are carried by a rod 28 secured in bracket 29 projecting from bearing '18. Une end of band 27 is pressed yieldably toward the other end by spring 3() confined between the band end'. and an adjusting wheel 31. By properlyadjusting the tension of spring 30, by means of wheel 31,l the drag of brakeband 27 on drum 26, may be varied as desired. The inherent friction in the rotating shafts and gearsv may sometimes be found to 4providesuiiicient drag onfthe glass sheet, in which case the brake is not used at all.

At the outer ends of shafts or pipes 8 and 6, are secured suitable connections, indicated generally at 32 and 33, for providing for the inflow and outflow of the cooling liquid. A handle 34, having a removable pipe extension 35, is secured tothe pivoted bearing 19 for shaft 6 to facilitate the disengagement of this shaft and roll from the sheet of glass 1, against the resistance of spring 21. i

It is to be understood that the mounting describedabove for apair of the idler rolls 5, is merely one approved form, and that many Nother variations of this mounting equally suitable for the purpose may be devised. The present invention resides in using these rolls as idlers andadding a brake to adjust the resistance of the rolls as maybe found necessary.

The preferred form of roll 5, as shown in Figs. 1, 2 and 4 is provided with a series of peripheral grooves and ridges 36 and 37, (see Fig. 4). These engage the molten glass as the sheet is being drawn and grip the same to counteract the narrowing tendency of the sheet. In Fig. 5 is shown the form of knurled rolls 38 now used in the Colburn process, and it is to be understood that this form of knurled roll is likewiseadapted for use with the idler roll assembly above. de-

scribed.

In Fig. 6 is .shown a horizontal sheet' drawing apparatus, in which the glasssheet 39 is drawn ofi' from a heated slab 40, and stretched under a fiattening roll 41, ,by .means of a drawing mechanism 42. This mechanism is described in detail in my copending application Serial Number 336,875, above noted, of which this application is a division in part, and in which the idler edge rolls here claimed were first disclosed and claimed. The edge rolls indicated at 43 in Fig. 6, are of substantially the same form as those already described in connecsheet drawin whether the sheet be drawn up, down or orizontally.

I claim:

1.111 a glass drawing apparatus, means for drawing a glass sheet from a mass of glass, and pairs of edge rolls engaging .the

sheet edges, adapted to be driven by the sheet passing between the rolls.

2.4In a glass drawingapparatus, means for drawing a glass sheet from a mass o for 'drawing a glass sheet, pairs ot idler rolls engaging the sheet` edges, and means for cooling the-rolls,

l3. In a glass drawing apparatus, means for drawing a glass sheet, pairs of idler rolls engaging the sheet edges, and means on the rolls for holding the sheet from drawing inward.

45. In a glass drawing apparatus, means for drawing a glass'sheet, pairs of idler rolls engaging the sheet edges, and meansfor frictionally retarding the rolls. 5. In a' glass drawing apparatus, the combination with means for drawing a glass sheet, of pairs `oi" cooled idler rolls engag ing the edges of the sheet.

6. In a glass drawing apparatus, the com-l bination with means for drawin a glass sheet, of pairs of cooled, circum erentially grooved, idler rolls, engaging the edges of .the sheet, v

7. In a glassdrawing apparatus, means for drawing a glass sheet from a masso molten glass, and a pair of idler rolls engaging each edge of the sheet at its source.

v 8. In a glass drawing apparatus, means molten glass, and a pair of cooled idler rolls engaging each edge of the sheet at its source. 9. n a glass drawing apparatus, means for drawing a glass sheet from a massv of molten glass, and a pair of cooled idler rolls, near the source of each edge of the sheet, between which the sheet edge is drawn.

10. In a glass drawing apparatus, means for drawing a sheet of glass from a mass of molten glass, and a pair of idler rolls near the source of each edge of thesheet between which the sheet edge is drawn, and means for rictionally retarding each Apair of rolls. 1

' 11. In agla'ss drawing apparatus, means for drawing a sheet of glass from a mass of molten glass, a pair of idler rolls near the source ofeach edge of the sheet between which the sheet edge is drawn, gears connecting the rolls whereby they are compelled to rotate equally and in opposite directions, and means for cooling the rolls.

12. In a glass drawing apparatus, means for drawing a sheet of glass from a mass of molten glass, a pair of idler rolls near the source of each edge of the sheet between f lwhich the `sheet edge is drawn, gears connecting the rolls whereby they are compelled to rotate equally and in opposite directions,

means for cooling the rolls, and means'for f frictionally retarding each pair of rolls.

Signed at Santa arbara, in the county of Santa Barbara and StateV of California, this 23rd day of February, 1921.

JAMES WHITTEMORE. 

